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Published on: April 19, 2019
Alkane isomers: presence in petroleum ether and complexity
I Lukovits1, J Fodor, A Gömöry
1Chemical Research Center, Hungarian Academy of Sciences, P.O. Box 17, H-1525, Budapest, Hungary. lukovits@chemres.hu
SAR and QSAR in Environmental Research
|July 4, 2006
Summary
Highly branched alkane isomers are less likely to be detected in petroleum ether. Their complexity, measured by topological indices, correlates inversely with concentration, suggesting a new experimental complexity metric.
Area of Science:
- Petroleum chemistry
- Organic chemistry
- Analytical chemistry
Background:
- Alkane isomer presence in petroleum varies with structural complexity.
- Complexity is currently an undefined, non-quantitative concept.
- Lack of experimental methods to quantify molecular complexity hinders analysis.
Purpose of the Study:
- To quantitatively define and measure alkane isomer complexity.
- To investigate the relationship between alkane structure and detectability in petroleum ether.
- To propose a new experimental measure for isomer complexity.
Main Methods:
- Gas chromatography, mass spectrometry, and infrared spectroscopy were employed.
- Topological indices and linear discriminant analysis were used for quantitative categorization.
- Concentration of isomers in petroleum ether was determined.
Main Results:
- A correlation was established between structural complexity and detectability.
- Highly branched alkane isomers were found to be less probable in petroleum ether.
- A quantitative relationship between complexity and concentration was identified.
Conclusions:
- Alkane isomer detectability in petroleum ether is inversely related to structural complexity.
- A novel experimental measure for isomer complexity, proportional to 1/concentration, is proposed.
- This study provides a quantitative framework for understanding isomer distribution in petroleum derivatives.
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